The present invention relates to an image-forming apparatus which is controlled to stop to avoid a situation where the adherence between toner of the image pattern α in the non-image area and a photoreceptor, intermediate transfer member or a second transfer roller increases, so as to keep the inside of the apparatus clean and to obtain clean images. Here, the image pattern α is an image which inevitably forms when an image forming operation has stopped or an image pattern created in the non-image area which comes after the image area before the image forming operation is stopped and used for optimizing the quality of the normal image by detecting the density, position, etc. of the image.
There is a well-known image-forming apparatus which forms a toner image on a photoreceptor having charging, exposing, and reversal developing means in its periphery, transfers (i.e. first transfer) the toner image onto an intermediate transfer member, and then transfers (i.e. second transfer) the toner image from the intermediate transfer member onto transfer material, such as transfer paper or the like used as recording material. This kind of apparatus uses a two-component developer which includes toner having the same charging polarity as that of the photoreceptor so as to perform reversible deposition. In order to prevent a two-component developer carrier from adhering to the photoreceptor, the developing bias is impressed before charging is started when an image forming operation starts and then the developing bias is turned off after charging has been finished when the image forming operation stops. This causes the toner to adhere to the area located before and after the charged area on the photoreceptor in a belt-like appearance. If the adhering toner (especially, the toner that has adhered when the image forming operation stopped) remains on the photoreceptor or the intermediate transfer member, the toner adherence increases causing an insufficient cleaning, which results in poor image quality when the next image is printed. Further, if the adhering toner remains sandwiched between two members or remains receiving heat from the fixing unit, etc., the adherence between the toner and a transfer member, such as an intermediate transfer member, photoreceptor, or a transfer roller, further increases causing an insufficient cleaning, which results in poor image quality. Furthermore, if the toner in the image area remains on a photoreceptor or an intermediate transfer member when transfer material, such as transfer paper or the like, jams, the same thing can happen. Especially, if the adhering toner remains sandwiched between two members or remains receiving heat from the fixing unit, etc., the adherence between the toner and a transfer member, such as an intermediate transfer member, photoreceptor, or a transfer roller, further increases causing an insufficient cleaning, which results in poor image quality. Those cases happen frequently.